A new lawsuit claims that airplane manufacturer Boeing and Southwest Airlines conspired to hide a fatal design flaw in the 737 Max jet. The negligence lawsuit was filed on Thursday, July 18 in the United States Eastern District Court of Texas on behalf of more than a dozen individuals who traveled on the airline until March of 2019, when all 737 Max jets were grounded following several high-profile plane crashes.

An article from Bloomberg Law claims that Southwest “obtained profits through a collusive relationship with Boeing, its sole airplane supplier.” By allowing individuals to fly on a jet with a known design flaw, the plaintiffs are claiming that Southwest defrauded not only its customers, but its own pilots and other employees as well.

The lawsuit claims that collusion began when Southwest strategically ordered several new jets from Boeing in an effort to economically benefit the airplane manufacturer; Southwest would achieve early access to new jet models in return. The article from Bloomberg Law goes on to say that the airplane manufacturer “rushed the defective 737 MAX 8 to market and Southwest helped to cover up the defect by assuring customers the plane was safe.”

Southwest continued to sell seats to thousands of customers despite allegedly knowing about the design flaw. The flaw in question relates to the automatic anti-stall system which is believed to have been the cause of two major crashes in Indonesia and Ethiopia that claimed the lives of 346 passengers and airline employees. The plaintiffs are stating that, had they been aware of the design flaw, they would not have purchased tickets for flights that would have put their lives in danger.

Southwest commented that they “intend to vigorously defend against the claims in the filing and strongly believe that the allegations made are completely without merit.” The airline claims that safety has always been its top priority for both passengers and employees. Boeing has yet to comment on the suit.

The lawsuit joins other legal claims against Boeing following the Indonesia and Ethiopia crashes, including lawsuits filed on behalf of the crash victims’ families that state Boeing failed to warn pilots and other officials about the flaw in the anti-stalling system, or MCAS. 737 Max jets continue to be grounded pending further investigations.